Chairs of this type are in very widespread use. One important example is a dentist's chair. Despite the great efforts made to design good chairs, existing items of medical furniture are not always able to provide the patient with the correct position for observation, diagnosis and treatment. The styling and design often cause medical complications during treatment. However, a significant, oft-neglected aspect is that the design and/or configuration of this furniture cause obstructions to the physician or other person carrying out treatment. This was stated by Prof. O. Hokwerda (Groningen University) during the congress “The Dentist as a Patient” in November 2001 in Enschede (NL).